Analysis/evaluation of motions of a player of sport has usually been performed by an instructor. For instance, when a golf player practices swings, an instructor watches the player's motion and gives appropriate advices. If such an instructor is not available, the player records his swings in VTR or films and shows them later to the instructor for advise.
There has been proposed a memory means which can pick up swing forms of a player in VTR or in time lapse shooting; for example, a technology which picks up swing forms of a player by an electronic-still-camera and reproduces/displays them in the unit of frames to viewers.
There has also been proposed in the prior art a system for evaluating golf swings which measures the speed or direction of a golf ball or the impact speed of a club head and digitally displays the result in numerical figures.
Although there is also available a system which picks up swings in image and processes them, there has heretofore been no system which can analyze the captured swings in real time, compare them with a reference, and give suitable advises. When a golf player wishes to practice by himself without an instructor, he cannot achieve an effective result because he is without valuable advises. Unless he is given timely advises while he still remembers his motion, his practice cannot attain effective result. If he is given instruction after a time lapse, learning effect cannot be fully achieved.
Even if a player is shown his swings in image which are reproduced in the unit of a frame, an amateur player merely sees his motions which he cannot evaluate properly and hence cannot benefit from the display. Data in numerics are not useful in evaluating his motions, since such display of numerical values alone does not show his whole actions nor diagnose his swings. All these conventional systems are therefore defective as a teaching system for golf swings.
Moreover, these prior art systems measure motions of a player by means of switches. More particularly, measurement is taken for 3 seconds after a switch is turned on; this takes unnecessary measurements before and after a motion. In order to eliminate such waste, the system requires manual operation by an assistant other than the player himself for turning on the switch. The conventional system, moreover, cannot precisely catch motions if they are very quick.
There has also been proposed a method of starting measurements by means of a sensor such as an optical limit switch. For instance, there has been proposed a method which employees a lamp and an optical limit switch and which uses signals generated when a golf club crosses the path as trigger signals for measurement. But this method is defective in that an optical limit switch should be provided at a designated location, and that the position of such switch should be changed depending on the type of motions to be measured such as the motion of impact and the motion of follow-through. The system therefore is not adaptive to the subject of measurement or the degree or type of motions. It is also difficult to use the system with an optical limit switch to measure complicated movements.
As stated above, the conventional systems require additional manual operations or special sensors, and the trigger method thereof is not flexible enough. They cannot effectively detect some types of motions.
This invention aims to obviate these problems encountered in the prior art and to provide a motion analyzing/advising system which measures, analyzes, and evaluates motions in real time and outputs the result in display to diagnose them without the special sensors, etc. for triggering the system, and which can efficiently and effectively start the measurement operation from the image information of the motions.